A Survey on Application of Building Information
Modelling in Road Construction
Amirkasra Honarpisheh
Submitted to the
Institute of Graduate Studies and Research
in partial fulfillment of the requirements for the Degree of
Master of Science
in
Civil Engineering
Eastern Mediterranean University
July 2014
Approval of the Institute of Graduate Studies and Research
Prof. Dr. Elvan Yılmaz Director
I certify that this thesis satisfies the requirements as a thesis for the degree of Master of Science in Civil Engineering.
Prof. Dr. Özgür Eren
Chair, Department of Civil Engineering
We certify that we have read this thesis and that in our opinion it is fully adequate in scope and quality as a thesis for the degree of Master of Science in Civil Engineering.
Assist. Prof. Dr. Alireza Rezaei Supervisor Examining Committee
1. Asst. Prof. Dr. Tülin Akçaoğlu
2. Asst. Prof. Dr. Mürüde Çelikağ
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ABSTRACT
Project management success is mainly evaluated by assessing the capability of managing time, cost, quality and nowadays, health and safety. Time and cost overruns can arise by various reasons in different projects especially roads and highways. These project types can also benefit from using Building Information Modelling (BIM) from the inception till the operation. Although the implication of BIM in building industry has been noticed theoretically and practically, its application in road and highway design and construction seems to be comparatively slower than building design and construction especially in developing countries such as Iran. Moreover, construction firms are still reluctant to admit changes even by facing delay and cost escalation in almost 100% of their roadway projects.
To understand better about the deviation in project constraints, a questionnaire was administered among 20 construction firms and they were asked to rate the given causes of delay, cost overrun and quality deviation in road projects and also to evaluate BIM efficiency in preventing the causes considering the basic definitions. Furthermore, a case project was studied to assess the reliability of findings and to determine how BIM can be applied to road and highway design and construction.
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Keywords: Project Management, Road and Highway Construction, Building
v
ÖZ
Proje yönetimindeki başarı, zaman yönetimi, maliyet, kalite ve son zamanlerde eklenen sağlık ve güvenliğin değerlendirilmesiyle belirlenmektedir. Özellikle yol ve otoyol projelerinde, zaman ve maliyet aşımları çeşitli sebeplerden dolayı ortaya çıkabilmektedir. Bu tür projelerde, projenin başlangıcından yapımına kadar Yapı Bilgi Modellemesi’ni kullanmak yararlı olabilmektedir. Genelde Yapı Bilgi Modellemesi’nin kullanımı kabul gorse de, özellikle İran gibi gelişmekte olan ülkelerde, yol ve otoyol yapımındaki uygulaması, bina tasarım ve yapımındaki kullanımına kıyasla oldukça yavaş ilerlemektedir. Buna ek olarak inşaat firmaları, yol yapımı projelerinin %100’ünde zaman ve maliyet aşımıyla karşılaşmalarına rağmen, değişimleri kabullenmekte isteksiz bir tavır sergilemektedirler.
Proje kısıtlamalarındaki değişimler konusunda bilgilenmek adına, 20 inşaat firmasına bir anket dağıtılmıştır ve onlara yol projelerindeki gecikme, fazla maliyet, kalite yetersizliğine neden olan etkenleri değerlendirmeleri istenmiştir. Ayrıca genel tanımları bağlamında, bu etkenleri önlemek adına BIM’in etkililiğini değerlendirmeleri de istenmiştir. Bunlara ek olarak, bulguların güvenilirliğini ve BIM’nin yol ve otoban tasarımı ve yapımlarındaki uygulanmasını belirleyebilmek adına bir vaka projesi üzerinde de çalışılmıştır.
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bulundurulduğunda, vaka çalışması BIM’in belirlediği sürenin %12’lik bir oranla daha doğru olduğu tespit edilmiştir.
Anahtar Kelimeler: Proje Yönetimi, Yol ve Otoyol Yapımı, Yapı Bilgi
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DEDICATION
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ACKNOWLEDGEMENT
I would like to appreciate my dear supervisor Dr. Alireza Rezaei for his masterly supports and guides on my master thesis research. His companionship helped me in all aspects of this research. I owe him for the many lessons I learned in construction management field, research methods and many more.
Besides, I would like to value Prof. Dr. Tahir Çelik who taught me the basics of project management. He made the opportunity for me to raise my academic knowledge.
Also I would like to thank my dear friend Mohammadnima Tazehzadeh for helping me a lot in this path.
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TABLE OF CONTENT
ABSTRACT ... iii ÖZ ...v DEDICATION... vii ACKNOWLEDGEMENT ... viiiLIST OF TABLES ... xii
LIST OF FIGURES ... xiii
LIST OF ABBREVIATIONS ...xiv
1 INTRODUCTION ...1
1.1 Background ...1
1.2 Research Question ...3
1.3 Aims and Objectives of the Study ...5
1.4 Works Carried Out ...5
1.5 Achievements ...6
1.6 Guide to Thesis ...6
2 BUILDING INFORMATION MODELING (BIM) ...8
2.1 Introduction ...8
2.2 What is BIM? ...9
2.3 Benefits of BIM ... 13
2.4 BIM Limitations and Risks ... 15
2.5 Literature Related to BIM... 18
3 ROAD CONSTRUCTION PROJECTS: PROBLEMS, CAUSES, CURES ... 22
3.1 Introduction ... 22
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3.3 How BIM Acts in Road and Highway Projects ... 26
3.4 Related Software ... 29
3.4.1 Autodesk Infrastructure Design Suite... 29
3.4.2 Bentley MXROAD Suite ... 31
4 METHODOLOGY ... 32
4.1 Introduction ... 32
4.2 Questionnaire Survey ... 32
4.2.1 Questionnaire Design ... 33
4.2.2 Pretest and Revision ... 34
4.2.3 Respondents ... 34
4.3 Case Study ... 36
5 DATA COLLECTION... 38
5.1 Introduction ... 38
5.2 General Characteristics of Respondents ... 38
5.3 Respondents Idea about the Detected Deflection Factors ... 39
5.4 Effect of Factors on Project Constraints ... 41
5.5 Respondents’ Knowledge, Familiarity and Usage of BIM in Projects ... 46
5.6 BIM and Its’ Ability to Integrate Drawings ... 46
5.7 Efficiency of BIM in Preventing Deflection Factors ... 47
6 CASE STUDY ... 49
6.1 Introduction ... 49
6.2 General specifications and details of the project ... 49
6.3 BIM modeling ... 51
6.3.1 Autodesk Infraworks ... 51
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6.3.3 Autodesk Navisworks Manage ... 51
7 RESULTS AND DISCUSSIONS ... 53
7.1 Introduction ... 53
7.2 Lack of Familiarity with BIM among Iranian Construction Firms ... 54
7.2.1 Advantages of using BIM in road and highway construction ... 54
7.2.2 Obstacles toward BIM adoption in road and highway construction ... 59
7.2.3 Recommendations toward BIM adoption in road construction ... 60
7.3 Controllability of Deflection in Project Triangle since the Early Beginning of the Project ... 61
7.4 3D, 4D or 5D BIM Models in Road and Highway Construction ... 63
8 CONCLUSSIONS AND RECOMENDATIONS ... 65
8.1 Introduction ... 65
8.2 Conclusions ... 65
8.3 Recommendations ... 66
8.3.1 Recommendations for future research ... 66
8.3.2 Recommendations for practitioners ... 67
REFERENCES ... 68
APPENDICES ... 74
Appendix A: Questionnaire sample ... 75
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LIST OF TABLES
Table 1: Potential benefit of using BIM for project managers (Allison, 2012) ... 19
Table 2: General authorities and specifications of Iranian construction firms ... 35
Table 3: Main characteristics of the respondents ... 39
Table 4: Respondents’ idea about the detected deflection factors frequency of deflection in projects ... 41
Table 5: Respondents’ knowledge, familiarity and usage of BIM in projects ... 46
Table 6: Efficiency of BIM in preventing deflection factors ... 47
Table 7: General details of case study project ... 50
Table 8: General specifications of the project ... 50
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LIST OF FIGURES
Figure 1: Project management triple constraints ...1
Figure 2: Level of effort, cost and effect in project life cycle ...4
Figure 3: The portion of waste of money in construction industry (Infocomm BIM Brochure 2010) ... 12
Figure 4: Level of cost, effect and effort in 2D drafting-centric workflow (Strafaci, 2008) ... 26
Figure 5: Level of cost, effect and effort using BIM workflow (Strafaci, 2008) ... 28
Figure 6: Questionnaire design workflow ... 34
Figure 7: Percentage of the respondents in terms of companies’ grading ... 36
Figure 8: Companies’ working experience and respondents’ level of education ... 40
Figure 9: Respondents’ assessment of deflection factors and frequency of facing time & cost overruns ... 41
Figure 10: Influence of detected factors on time overrun ... 42
Figure 11: Influence of detected factors on cost escalation ... 43
Figure 12: Influence of detected factors on quality deflection ... 44
Figure 13: Influence of detected factors on health & safety ... 45
Figure 14: BIM workflow in Design-Tender-Build contracts... 56
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LIST OF ABBREVIATIONS
BIM Building Information Modeling
AEC Architectural, Engineering and Construction
COBIE Construction Operation Building information Exchange AVS Audio Visual Software
FGI Focused Group Interview GIS Geographic Information System KSU Kent State University
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Chapter 1
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INTRODUCTION
1.1 Background
Project management success is mainly evaluated by measuring time and cost (also known as schedule and cost). Summation of these two criteria and scope are recognized as project management triangle which is illustrated in Figure 1. However, quality and health and safety are known as fourth and fifth criteria considered in project management (Çelik, 2010).
Figure 1: Project management triple constraints
As these criteria are relatively connected to each other, deflection in one item might result in a change in others. For instance, change in project scope might affect the project time and probably the project cost. Time and cost overruns might arouse by various reasons and causes in different projects especially roads and highways which are larger in size. Causes such as change order in drawings and specifications,
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material shortage, improper planning and management etc. affect road and highway projects more due to their size and complexity. These types of projects can also benefit from Building Information Modeling (BIM) as a design and management tool from inception till operation. Genesis of Building Information Modeling returns to mid-2005 when the US General Services Administration (GSA) made its decision to build a new courthouse in Jackson, Mississippi with the total area of 410,000 square feet (Robert L. R., 2011). Since that time, 2D and 3D software were used for design, documentation and planning during all construction phases in building industry. This differs a bit in road and highway construction while it has been just a few years that application of BIM in road construction is proposed. By this technology, visualization and communication of design and construction process can be supported somehow. This might be so efficient due to pre-evaluating design choices and choosing the best through the inception phase. Moreover, more accurate cost estimation and better planning in construction and waste management will be resulted by applying BIM workflow.
Though the benefits of applying BIM in building design and construction have been noticed theoretically and practically, its application in road and highway design and construction seems to be comparatively slower than building industry especially in developing countries such as Iran. Moreover, construction firms are still reluctant to admit changes even by facing delay and cost escalation in almost 100% of their roadway projects. Besides, the various advantages of adoption of BIM in horizontal constructions are not evident.
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causes of delay and cost escalation in road construction projects from the contractors and consultants’ points of view. It was also tried to observe the extent of familiarity with BIM among Iranian construction firms and the degree they thought BIM will be efficient to prevent mentioned causes of time and cost overrun. After completing the results of the questionnaire survey, a case study was analyzed to find out how real the results of the questionnaire were. In this case study, a completed road project in Iran was modeled and scheduled by BIM-based software programs.
The questionnaire results presented a ranking for the detected causes and factors of time, cost and quality deflection in road construction projects. Also a very low degree of knowledge on BIM was found among respondents. Therewith the case study implied that change orders applied to project would probably not have happened by using BIM during design phase. Furthermore by having an accurate cost estimations and scheduling, gaps and ceases in the execution phase during the last two years could have possibly be avoided in most cases.
1.2 Research Question
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have their own satellites with the ability to prepare high quality images of the ground. The last to be mention here is the connection and uniformity between the design, detailed design and documentation steps in BIM process. In contrast with the traditional 2D drafting-centric design in which each step should be finished in order to start next step, within BIM workflow, these steps can be followed simultaneously. This will lead to more collaboration, less time consumption and also less risk of human error in case of updating any needed change. Figure 2 demonstrates the difference in level of effort, cost and effect during the life cycle of project by using BIM or 2D drafting-centric workflow.
Figure 2: Level of effort, cost and effect in project life cycle
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1.3 Aims and Objectives of the Study
In order to answer the research question as the aim of this study, a number of objectives were determined as listed below:
1. To inquire the level of knowledge on BIM among road and highway consultants and contractors.
2. To specify the percentage of road projects in Iran which face delay and cost escalation.
3. To evaluate the list of factors which affect time and cost overrun in road and highway projects in Iran from construction firms point of view.
4. To investigate the level of efficiency of BIM in preventing deflection factors. 5. To find out the financial benefits of using BIM in road and highway projects. 6. To estimate the amount of time which can be saved by using BIM.
1.4 Works Carried Out
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1.5 Achievements
As stated by the survey contributors, BIM could be very useful in controlling causes of delay, cost overrun and quality deflection in projects. Although the traditional 2D drafting-centric methods seem to be no longer beneficial in the current design-tender-build system in Iranian road construction society, still there is reluctance toward implementing new concepts due to wide range of causes such as high preliminary costs, lack of expert staff etc. Also in the path of importing new technology, a strong supervision and legislative governmental institution is needed.
Case study shows a various percentage between 7 to 40% more accuracy in cost estimations between considered items. Furthermore change orders imparted in some sections of the project, added about 1.8% of the total project cost mentioned in the contract which might have not been occurred by using BIM.
1.6 Guide to Thesis
After the introduction, chapter 2 focuses on basic definitions of Building Information Modeling (BIM) and the related literature. Further studies on BIM abilities, applications, benefits and limitations all over the world are the scope of this chapter.
In chapter 3, the main challenges and obstacles in road construction will be discussed considering their consequences. Furthermore, the causes will be brought up and finally the cures will be presented which is one of the main aims of this survey.
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respondents will be provided thereafter and finally an explanation on the case study will be presented.
Chapter 5 presents the results and outputs generated by the questionnaire survey. Respondents include two groups of Iranian contractors and consultants although the results are integrated. The chapter includes the main topics asked from the respondents.
In order to prevent disorder, all data related to the case study project were brought in chapter 6 separately. The first part of this chapter contains general specifications and details of the case project. After that in the second part, BIM modeling procedure done in this survey are explained.
In the first part of chapter 7, relevant discussions around the findings of questionnaire survey will be presented. Results of each part of the questionnaire will be checked separately in order to find out the advantages of the positive points. The second part of this chapter contains a case study including modeling a constructed road project in Iran in order to evaluate the usage of BIM workflow in road and highway construction field.
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Chapter 2
2
BUILDING INFORMATION MODELING (BIM)
2.1 Introduction
The concept of BIM has existed since 1970s. Although the appearance of the term Building Information Modeling, the popularity of BIM started after releasing a paper entitled “Building Information Modeling” by Autodesk company in about 2002. Genesis of Building Information Modeling returns to mid-2005 when the US General Services Administration (GSA) made its decision to build a new courthouse in Jackson, Mississippi with the total area of 410,000 square feet. Since that time, 2D software were used for designing and documentation during all construction phases while GSA inquired its staff to shift from familiar 2D to the three dimensional approach (Robert L. R., 2011).
Building information modeling (BIM) has been defined diversely by various authors. Considerably these definitions are based on process or product.
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Further studies on BIM abilities, applications, benefits and limitations all over the world are the scope of this chapter.
2.2 What is BIM?
Building Information Modeling (BIM) perhaps is one of the most emphasized concepts in the Architecture, Engineering and Construction (AEC) industries nowadays. AEC industry has continued informing its association segments, members and stakeholders about BIM adoption in various paths.
Unlike other digital technologies affiliated by the building industry, BIM has altered the way buildings are designed, built, assembled, commissioned, operated and maintained (Sharag-Eldi and Nawari, 2010). By the definition, Building Information Modeling (BIM) workflow is able to create live and intelligent three-dimensional parametric models. These models can become a 4D model by being linked to time and also a 5D considering financial data links. Contemplating all project contributors (architect, engineer, contractor, subcontractor), BIM is aimed to resemble all physical and functional characteristics of the structure true to scale.
As the software is capable to detect conflicts between different parts included, these models are known as "live" models. Moreover, BIM uses a pre-considered database including all contributed structure's elements. For example, if the designer chose to add a wall to the model as a component, the best suited wall considering the necessary characteristics can be chosen from the list of pre-programmed walls.
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change. Furthermore, BIM is able to attach the input data to the model and information is produced automatically by using a centralized mechanism for the project information (Monterio and Martins, 2013).
In order to go through these innovations in BIM, each feature will be explained more with its benefits:
1. 3D Design: By the help of this type of design, customers will get the chance to visualize the project and see the project site with respect to the project construction (GSA BIM Guide, p.14).
2. 4D Design (Time): Integrating project construction phases and sequences to the 3D model, 4D model is resulted with the ability of visualizing the sequence of the construction. This 4D model can contain various level of details in order to be used in different phases of the construction by owners, subcontractors, etc. (GSA BIM Guide, p.2, 3).
3. 5D Design (Cost): By adding the project costs to the mentioned model, BIM mode will be able to print out the Quantity Take-Offs (QTO) and cost estimations including the relationships between quantities, costs and locations.
4. Collision Detection: BIM software is planned to examine the model in order to find spatial and sequential conflicts. In case of finding any clashes, automated notifications will be sounded.
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6. Energy analysis: By this capability, BIM will provide the user with a detailed accurate energy modeling.
What can be seen is that BIM is adopted more and more every day among contractors, engineering firms and architects. According to McGraw-Hill (2010), approximately 23% of contractors had used BIM in at least 60% of their projects in 2008 in the USA while this amount had risen to 38% in 2009. Referring to Infocomm BIM brochure (2010), two major facts are involved:
1. Building industry consumes a massive percentage of our resources each year. As a limited amount of these resources are recycled materials, stakeholders hope that BIM will be a solution for this problem in early future.
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Figure 3: The portion of waste of money in construction industry (Infocomm BIM Brochure 2010)
Furthermore, BIM is not only limited to drawings. It is a combination of design, construction and maintenance information and data reservoir as a model which can be shared with all involved members. In order to propagate project success using BIM, it is better for these members to use a combination of BIM and Integrated Project Delivery (IPD). IPD is an alternative for the traditional contract methods like design-bid-build and design-build. As far as all stakeholders share the risk in design and build process and also the profit of growth in productivity in IPD, a precise BIM integration will help the system to work well. This is why the term "drawing" is being replaced with the buzzword "modeling" gradually.
The prevailing BIM platform for AEC contributors is Autodesk Revit these days. But Revit is not the only choice of architects and building owners. In United States Bentley BIM also has been used frequently by the AEC counterparts while Graphisoft, Tekla structure, Solibri model checker, Nemetschek etc. are in the next seats for the users worldwide (JBIM, Fall 2012).
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2.3 Benefits of BIM
Theoretically speaking, BIM has expressed to be advantageous in both geometrical modeling of a building's performance and management of construction projects (Bryde, 2012). BIM has a separate usage in all phases of the project life-cycle: it is used by the client in order to find out the project needs; by the design team to analyze, design and develop the project; by the contractor in the way of project management and late in the operation phase by the facility manager (Grilo and Jardim-Goncalves, 2010). One of the most important issues caused by BIM is the collaboration between the different members of the construction team. This collaboration will eventuate in:
1. Decrease of the hazy shades between design drafts and constructability. 2. Speeding up the production which will lead to earlier completion of the
project.
3. Giving the construction manager a better chance in quality control considering the incorporation of design, engineering and construction.
4. As the quantities resulted from BIM are more accurate, there would be a better chance for the members in order to prepare cost estimations.
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Some other advantages that have been delivered by BIM include but not limited to the availability of the plans, elevations and sections which are produced as "views" by generating a single design model. On the other hand, BIM is capable of modifying the changes in the model. As an example, if a change happens in one of the details, all the related details will be updated automatically to be correspondent with the changes.
As it is expressed in the technical report of the Stanford University Center for Integrated Facilities Engineering (CIFE), five important benefits resulted by using BIM in 32 major projects include (CIFE, 2007):
Up to 40% elimination of unbudgeted change.
Cost estimation accuracy within 3%.
Up to 80% reduction in time taken to generate a cost estimate.
A saving up to 10% of the contract value through clash detection.
Up to 7% reduction in project time.
As a brief, these five benefits are the result of a set of critical information within each major phase of the construction lifecycle including design, construction and management. By using BIM, this information will be available classified as follows (Autodesk, 2003):
In the design phase these information include the design, schedule, and budget information.
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And finally in the management phase, performance, utilization, and financial information are offered.
2.4 BIM Limitations and Risks
A great modification in communication amongst AEC team members and stakeholders can obviously be seen by using BIM. While BIM is one of the most desirable assets in construction industry, there are some essential considerations and limitations that should be observed in order to have a successful use. A list of these inherent limitations is given below (Infocomm BIM brochure, 2010):
1. Cost of software and hardware: Currently most AEC companies have applied a version of Audio Visusl (AV) software including 2D or 3D CAD drafting. It is obvious that the cost of procurement, maintenance and renewing the software must be taken into account. However, BIM packages seem to be more costly than ordinary CAD software. Furthermore, unlike CAD software which can be even operated simply by a laptop, in respect to the basic introduction of BIM, more equipped workstations are needed. Usually the exact needs for BIM software are recognized in the “Getting Started section”. 2. Cost of training: Regardless of how expert are the staff in using current
software, there should be a quick and efficient training for all related members of a company which desire to use new software. This should be done simultaneously while current activities are in progress in the company. 3. Transition from drafting to modeling: Transferring from a simple CAD
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4. Compatibility between software platforms: The inter-product compatibility is probably the most important problem with the BIM adaptors. It should be mentioned that all team members within the project should use a compatible version of software with the others in order to increase the interoperability. An easy solution for a company is that to manage all members to use a single format.
5. Innovation: As far as BIM is aimed to allocate parameters to intelligent objects in order to progress the output, there is a potential to interdict innovation which would probably occur without the automated processes that BIM now provides otherwise.
In order to reduce the limitations discussed above, it is serious to take some situations into account before the project starts and make a few agreement within the company to evaluate the risks and control them in case of happening. These agreements include:
1. Liability: One of the most important things in AEC projects is cooperation. The responsibilities of project participants should be defined prior to the project start while the limitations for contributing the model by different members must be determined. To decrease the liability risks, contractual relationships should be considered and level of liability should be defined for all members.
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Also confidential issues should be addressed at the beginning of the project. "Regarding the number of project participants, it is required to determine if it is even possible to assert confidentiality or ownership". 3. Data transfer: Nowadays a variable set of BIM programs is available for
applicants. Since it is scarce that all project participants use the same software, some problems might occur in data transfer. There is a question still left here that considering this problem, is the data yet precise?
4. Software malfunction: Unexpected misdeed risks always exist in all technologies which can cause the data irremediable or inaccessible. That is why it is so important to have always a backup of the software and data since the software company is not always liable for the software malfunctions.
Moreover, as the system is intelligent, it can make some changes to the model in case of finding clashes and it may cause some problems in real life construction if the changes do not have the sufficient accuracy.
The recommendation to the companies in construction industry which have chosen BIM is that consider the challenges of using building information modeling and do the necessary arrangements within the company before starting the projects with BIM so that they can minimize these potential risks of BIM.
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2.5 Literature Related to BIM
Since the beginning of the theories on building information modeling, there have been a lot of researches and surveys done by many people trying to find out capabilities, risks, benefits etc. of BIM. Still after 8 years, there have been many questions left without answer because of the wide domain of the field and the relations between BIM and other related issues. This section goes through a limited up to date surveys being conducted worldwide.
Given the benefits to project documented in the case studies, it is a questionable point why there has not been a greater take up of BIM on construction projects (Bryde et al., 2012). Bryde et al. (2012) made a survey in order to explore the limit of usage of BIM lead to reported benefits in construction project. By gathering the secondary data of finished construction projects that have used BIM in their projects, it is concluded that a precise cost/benefit analysis is required ensuring the practitioners about investing on BIM. Although the price of common BIM software is somehow the same as analogous software in CAD platform, still the maintenance and initial costs of BIM is significant especially for new established and smaller companies. But for sure it can be said that by succeeding in BIM usage and increasing the productivity, Return on Investment (ROI) is something inevitable.
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Table 1: Potential benefit of using BIM for project managers (Allison, 2012)
Potential benefits
for PMs Why?
Organize the project schedule
and budget
An integrated 5D model immediately updates both the schedule and budget when any design change occurs Work well with the
design team
By using the integrated 5D BIM model to visualize and explore the impact of changes, s/he can keep project scope in
check and become a trustworthy liaison between the designer and owner
Hiring and controlling the subcontractors
Having a handle on clash detection and coordination plays a key role in keeping sub-contractors' work predictable Requests for
information and change orders
Utilizing coordination resolution in preconstruction, these numbers can be brought to near zero
Optimize the owner experience
and satisfaction
Owner received a big injection of confidence in the GC when the PM showed him/her design decisions impacted
cost and schedule Project closeout
PM to present a 6D BIM- a facility resource with information on warranties, specifications, maintenance
schedules, and other valuable information Profit margin
By thoroughly understanding the project in 5D, the PM has more tools at his disposal to keep tight reins and more
reports to monitor progress Progressive owners
are mandating BIM on their projects
Becoming the BIM expert, in both preconstruction and out in the field, makes the PM invaluable and key player. PM firm growth
Project's success with 5D means the opportunity to grow the firm's reputation and helps the corporate team win new
business.
2: Potential benefit of using BIM for project managers (Allison, 2012)
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Eadie et al. (2013) tried to measure BIM implementation throughout UK construction project life cycle. They found the collaboration aspects as the most important impact. Considering 92 responses from BIM users, they mentioned collaboration (ranked first), management aspects (ranked second), reduction of waste (ranked third), accuracy (ranked forth) and less significant than those visualization as the impacts of BIM in construction lifecycle. "Finally the research indicated that the main reason for not adopting BIM on current projects relates to the lack of expertise within the project team and external organizations". Akcamete et al. (2011) demonstrated that facility managers’ duty in operation and maintenance of construction projects is about 60% of the total costs of the project. Khanzode et al. (2008) states a 1% to 2% reduction in costs of Mechanical, Electrical and Plumbing engineering (MEP) systems in a large-scale healthcare project due to contractors’ specialist expressions.
Gu and London (2010) analyzed the readiness of industry in adopting BIM regarding people, product and processes as the main criteria. They found both technical and non-technical subjects that needed to be noticed. By using the Focus Group Interviews (FGI) method, they derived that due to the development of construction industry and the need for collaboration, the broader adoption of BIM in the AEC industry is very promising.
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process is not upstanding and direct and also strict rules need to be pursued to have an accurate result.
From a different point of view, benefits of presenting BIM in AEC education have been discussed in the USA. "The main objective of this studio is to provide students with means through which integrative pedagogical objectives are achieved through BIM" (Sharag-Eldin and Nawari, 2010). The introduction of BIM at Kent State University (KSU) and University of Florida (UF) eventuated that BIM can deliver educational build environment which will lead to an interoperable format that integrates design and construction comprehension.
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Chapter 3
3
ROAD CONSTRUCTION PROJECTS: PROBLEMS,
CAUSES, CURES
3.1 Introduction
It has been years that construction industry is been used by different societies as a tool in order to develop their urban and rural spaces (Enshassi et al., 2006). This is more obvious in developing countries and probably leads to development of economy.
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In this chapter, first the main challenges and obstacles in road construction will be discussed considering their consequences. Furthermore the causes will be brought up and finally the cures will be presented which is the main aim of this survey.
3.2 Challenges, Obstacles and Their Causes in Road Construction
The main purpose of this study is to identify which factors are considered as challenges and to a lesser degree the causes behind them. The first step is to address the problems, challenges and opportunities. However, there is a wide range of challenges considering the source and it is not the subject of this study to discuss all; just some amendable related parts have been brought up.It is obvious that all researchers and specialists have divided the main obstacles in large construction and infrastructure projects into main categories of time overruns and cost escalation and tried to study the issue from different points of view including contractor side, consultant side and owner’s side. In all findings, a root of poor managing can be seen, which is a subsequent of many reasons.
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management, providing quality workmanship etc. Flyvbjerg (2007) found inadequate risk assessment factor as the most important problem in Denmark infrastructure projects like Copenhagen Metro which resulted in financial risks. Kaliba et al. (2008) found cost overruns, schedule delays and the need to improve management of projects as the most important issues in road construction in their country Zambia. Odeh and Battaineh (2002) also considered improper planning and slow decision making among the top 10 main problems of contractors in large size projects which might result in construction delay in Jordan. Al-Momani (2000) conducted a survey between 130 public projects in Jordan and found also the designer role and user changes important in the causes of delay. In Saudi Arabia, Assaf and Al-Hejji (2006) identified 73 causes of delay and concluded the most common problem recognized by the consultants, contractors and the owners as “change orders”. Mezher et al. (2006) studied the subject from the viewpoints of contractors, consultants and owners separately. According to their findings, owners are mostly faced to financial issues while contractors voted for contractual relationships as the most important problem and consultants mentioned management issues. Moreover Abd-Majid and McCaffer (1998) conducted a survey on the causes of contractors’ performance delay in the United Kingdom. Their findings indicated materials, equipment and labor-related delays as the major causes by that time.
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(2004) concluded that projects with longer implementation phases seem to have a larger cost escalation and sluggish projects are usually more expensive.
Therefore, it is so overt that all the ability should get to work in order to make a proper preparation and to conduct an explicit planning and authorization before the owner makes his/her decision to start the project. Strong and solid risk assessment, documentation and forecasting would be necessary to be on budget and on time.
The question is how to reduce inaccuracy and risk in forecasting?
In order to have a better understanding on what is presented below, it would be useful to take a look at the procedure which has been used for design and constructing of road and highway projects for the past 10 to 20 years first called 2D drafting centering design workflow. The method starts with the preliminary design. Completing this step, detailed design takes place and then on to construction documentation. Each step has to be completed before the start of the next step. Regardless of the separation between the steps, this process will play the role properly until the usual unavoidable design change should be done. This is where the time-consuming and error-prone process of manual drafting process is needed to be made. Figure 4 demonstrates the level of cost, effect and effort in 2D drafting-centric workflow. Strafaci (2008) has tried to compare the Building Information Modeling with the traditional method in road and highway design and construction and to check the extent it would be found helpful.
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projects. Thanks to technology development, companies like Autodesk or Bentley have provided us with software to perform BIM workflow in road and highway project. Software products like Autodesk Infrastructure Design Suite or Bentley MXROAD Suite are solutions for planning, designing, building and managing heavy construction projects. But still construction firms are using the traditional methods instead of BIM regardless of the many benefits of it.
Figure 4: Level of cost, effect and effort in 2D drafting-centric workflow (Strafaci, 2008)
3.3 How BIM Acts in Road and Highway Projects
Today, BIM is one of the hottest subjects in the infrastructure both for governmental projects and private sector. Practically speaking, utilization of BIM workflow in road and highway projects starts with creation of an intelligent 3D model of the highway in which the components are linked to each other dynamically; this means a set of coordinated, reliable design information of the project together in a single file. This model-based design method gives the opportunity to take different design alternatives into consideration in order to reach the optimal one. Regardless of drawings including lines, arcs, etc., the chance of easier designing of complicated road and highway features like junctions and curves is given. Another advantage of Figure 4: Level of cost, effect and effort in 2D drafting-centric workflow (Strafaci,
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this wizard-based design tools is the ability to implement the late stage design changes in a short time and benefit from the automatic update system in all documentations such as bills of quantities, schedules etc. incorporating all the edits. Moreover, the clash detection technology used in Building Information Modeling in buildings to meet the interferences between water, structural, HVAC and other subsystems can be used effectively in road design and construction to prevent clashes with underground infrastructures water and sewerage systems, electric and telecommunication cables etc.
But unlike the vertical structures, BIM is much more than intelligent 3D model for horizontal constructions such as roadways. It can be used in simulating lighting, lines of sight, drainage, signage and many things more and of course at the center of attention, in construction planning and scheduling which the whole thing might lead to prevention of costly errors before a project even goes to site. Another advantage of using BIM in horizontal construction is the more complicated situation of this type of projects than building structures because of the correlation with ground topography and existing infrastructure unless in tall buildings, regardless of one or two ground level floors and foundation, other floors are usually typical and identical. This makes believe that roads can even benefit more than buildings from BIM as a matter of this complexity.
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years of construction period, planning played an acute role in this project (Skanska, 2011).
The benefits of BIM in road construction projects can be summarized as:
Evaluation of design alternatives is much easier with BIM.
Design for the objectives such as constructability, sustainability and road safety can be optimized by using the simulation and the information model.
Design deliverables such as 2D plans and documentations, quantity take offs, as-built drawings and comparisons, operations, construction sequencing and also operations and maintenance can be achieved directly by using a BIM workflow.
Figure 5: Level of cost, effect and effort using BIM workflow (Strafaci, 2008) As presented in Figure 5, design for the objectives such as constructability, sustainability, road safety etc. can be optimized by using the simulation and the information model. For instance, two of these criteria are described more:
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Road Safety – There are many factors in driving design such as sight distance, safe speed, longitudinal and latitudinal slopes etc.; traditional analysis in these fields are based on mathematical equations which include vertical curvatures and slopes, however there are some inefficiencies in this method like visual obstructions. This is the point which integration of 3D model visualization and simulation helps civil engineers to recognize the barriers before the inception phase.
Constructability – Most often civil engineers and designers do not consider constructability in design phase and just focus on code compliance. This might occur as false explanations on design content because of poor documentation and probably might end in change orders and extra cost and time.
3.4 Related Software
Although the method of Building Information Modeling has been used since the previous decades, still the application in road and highway design and construction has been rather gradual comparing to building construction.
Today all members involved in construction industry face tight timelines and budgets especially considering the competitive and tough economy. In order to be accurate in specifications, on budget and around the clock, some computer software with the content of BIM have been offered by reputed companies such as Autodesk and Bentley. Here it has been decided to take a quick look at these new products’ functions.
3.4.1 Autodesk Infrastructure Design Suite
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Infrastructure Design Suite, variable application will be found for different stages of the project lifecycle. In order to move forward through the purpose of this study, three main areas have been considered.
1. Planning and early design
2. Documentation and detailed design 3. Construction simulation and management
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3.4.2 Bentley MXROAD Suite
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Chapter 4
4
METHODOLOGY
4.1 Introduction
In all surveys and researches, methodology is a need in order to answer two main questions:
How the surveyor has created or collected the needed data?
How the surveyor has analyzed the collected data?
Methodology is the discussion of analysis of method applied to the survey. By means of good methodology, the researcher will succeed in providing the relative data with the minimal time and cost expenditure.
Coming up after introduction, selected methods being used in this survey will be explained. Preparation and finalizing the questionnaire will be detailed. A brief about the respondents will be given after and finally an explanation on the case study being held in this survey will be presented.
4.2 Questionnaire Survey
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4.2.1 Questionnaire Design
A set of closed ended questions including multiple choices and matrix form were defined in order to have more accurate results. The questionnaire was divided into two main parts. In the first part, general information of both respondents and company were asked. All respondents were requested to state their experience in road and highway construction, grade of the company and some other basic information. The second part mainly included the discussion on 13 factors such as change order in design, poor design, poor management etc. which had been found effective on time and cost overruns and the assessment on preventing them. The whole 13 mentioned factor are brought in chapter 5 through the next chapter. These 13 factors were chosen from a list of detected factors through the existing literature on road and highway construction. For the effect of each factor the severity was categorized on a five range scales as follows: least important, less important, important, more important and most important on a 0 to 100 point scale. Also for the efficiency of BIM in preventing mentioned factors, the same categorization was used.
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Figure 6: Questionnaire design workflow
4.2.2 Pretest and Revision
It is so important to assure that the respondents understand the questionnaire contents completely. As a result, before emailing the questionnaire to the main target population, 3 postgraduate students of the Construction Management group of the Eastern Mediterranean University were provided with the first copies of the questionnaire to find out if there are any problems and defects understanding the main idea. In this stage, respondents were interviewed one by one to discuss on the fluency and clearness of the questions. The revision of the first draft was finalized and prepared to be sent to the main target population.
4.2.3 Respondents
186 companies were membered in the Iran Road Construction Association at the survey period. The questionnaires were emailed to approximately 11% of these members (equal to 20 road construction firms) as the target population of this study. 66.67% of the respondents had a grade 1 company while 16.67% had grade 3 and the same percentage had grade 4. Table 2 demonstrates the general authorities and
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capabilities of different grades of construction firms in Iran including maximum allowed costs and maximum allowed number of projects per year. Figure 7 shows the percentage of the respondents in terms of companies’ grading for both contractors and consultants.
Table 3: General authorities and specifications of Iranian construction firms Construction company's
grade
Number of projects allowed per year
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Figure 7: Percentage of the respondents in terms of companies’ grading
4.3 Case Study
In order to validate the results of the questionnaire survey, it was decided to conduct BIM workflow on a constructed road project in Iran as a case study. Generally, case study research method is used to diagnose the accuracy of presumed or resulted data
0 10 20 30 40 50 60 70 80 1 2 3 4 5 P er centa ge & f requenc y Contractors' grade
Percentage of contractors considering grade
frequency percentage 0 10 20 30 40 50 60 1 2 3 P er centa ge & f requenc y Consultants' grade
Percentage of consultants considering grading
Frequency Percentage
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in real-life situation. According to Schell (1992), case study is the best research pattern to accredit the specs of an empirical event in real-life.
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Chapter 5
5
DATA COLLECTION
5.1 Introduction
This chapter will present the results and outputs generated by the questionnaire survey. Respondents included two groups of Iranian contractors and consultants; however, the results are integrated. The chapter is based on seven subheadings which are the main topics asked from the respondents. Totally twenty responses were gathered from twelve contractors and eight consultants related to the field.
Sureveymonkey website was used in order to provide the respondents with easy access to the questionnaires in Iran and finally the responses were analyzed and validated by IBM SPSS Statistics Data Editor Version 22.
5.2 General Characteristics of Respondents
39 Table 4: Main characteristics of the respondents
Main Characteristics of the respondents Frequency (#)
Percentage (%)
Companies' line of business Contractor 12 60
Consultant 8 40 Contractors' grade One 8 66.67 Two 0 0 three 1 8.3 Four 3 25 Five 0 0 Consultants' grade One 4 50 Two 1 12.5 three 3 25
Company's working experience
Less than 10 years 7 35
10 to 20 years 2 10
20 to 30 years 6 30
More than 30 years 5 25
Respondents' education degree
Bachelor degree 1 5
Master degree 12 60
PHD 7 35
5.3 Respondents Idea about the Detected Deflection Factors
In the second part of the questionnaire, participants were asked to express their idea about the 13 detected deflection factors in this listed as:
40 9. Poor risk identification
10. Late clash detection 11. Poor coordination on site 12. Shortage of material 13. Slow decision making
Figure 8: Companies’ working experience and respondents’ level of education Excluding financial issues, a list of 13 main causes of time and cost overrun in the highway projects had been presented for the respondents and they were asked to represent their assessment on the extent of controllability of these factors. Furthermore, the frequency of facing time and cost overruns and quality deflection was questioned which the results are shown in Table 4 and Figure 9.
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Table 5: Respondents’ idea about the detected deflection factors frequency of deflection in projects
Respondents idea about the detected deflection factors Frequency (#)
Percentage (%)
Assessment on the factors
Controllable 10 10
Uncontrollable 50 50
Frequency of facing time & cost overruns in the projects
Usually 13 65
Always 7 35
Figure 9: Respondents’ assessment of deflection factors and frequency of facing time & cost overruns
5.4 Effect of Factors on Project Constraints
In the next step, participants were requested to score the influence of the detected factors on project constraints including time, cost, quality and health and safety between the ranges of 1 to 5 with 1 as the minimum amount (0-20%) and 5 as the maximum (80-100%). Figures 10, 11, 12 and 13 demonstrate the allocated scores by the respondents. 0 10 20 30 40 50 60 70
Factors are controllable Factors are
uncontrollable
Usually facing deflection Always facing deflection
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Figure 10: Influence of detected factors on time overrun
As it can be seen, around 70% of the participants selected the level of importance of 4 of 5 for slow decision making on time overrun while about 50% found change order in specifications and poor documentation in the level of importance of 2 of 5.
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Figure 12: Influence of detected factors on cost escalation
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Figure 14: Influence of detected factors on quality deflection
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Figure 16: Influence of detected factors on health & safety
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5.5 Respondents’ Knowledge, Familiarity and Usage of BIM in
Projects
In the subsequent questions, it was aimed to check the respondents’ familiarity with BIM as a secondary tool in project management. Unfortunately, the results showed an undesirable file. Among the participants, only 20% expressed that they have very good knowledge on the issue while almost 35% had hardly heard about Building Information Modeling before. The worst case is that around 85% had rarely used BIM before. Table 5 represents the results in this step.
Table 6: Respondents’ knowledge, familiarity and usage of BIM in projects
Respondents knowledge and familiarity with BIM Frequency
(#)
Percentage (%)
Extent of familiarity with BIM
Fair 7 35
Good 9 45
Very good 4 20
Excellent 0 0
Extent of using BIM in projects Hardly ever 17 85
Occasionally 3 15
5.6 BIM and Its’ Ability to Integrate Drawings
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equality in this case where 57.14% found BIM workflow very useful while 42.86% assessed as somewhat useful.
5.7 Efficiency of BIM in Preventing Deflection Factors
The last part of the questionnaire included a matrix question to investigate the efficiency of BIM in preventing deflection factors. The ability of integrating the 3D model with time and cost as the 4th and 5th dimensions was explained. After
mentioning a few advantages of 4D and 5D models, respondents were requested to evaluate the efficiency of using BIM procedure in preventing reflected factors. Table 6 contains the detailed results of the final case.
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Chapter 6
6
CASE STUDY
6.1 Introduction
In order to prevent disorder, all data related to the case study project were brought in this chapter separately.
After introduction, the first part of this chapter contains general specifications and details of the case project. After that in the second part, BIM modeling procedure done in this survey are explained.
6.2 General specifications and details of the project
The project started in July 2002 with the estimated cost of 60,325,299,000 Rials (approximately 1,856,163$). Although the project was supposed to be finished by February 2006, it finished in December 2007 with the total cost of 75,323,927,745 Rials (approximately equal to 2,317,659 $) which shows a 14,998,628,745 Rials (461,496$) cost overrun equal to 24.8% of the estimated cost and also a 23 months period delay in time which is equal to 55% of the total estimated project time.
50 Table 8: General details of case study project
Project name Tehran – Pardis Highway, third segment
Client Iranian Ministry of Roads and Transportation
Consultant Iran Oston Consulting Engineering Co.
Contractor Iranian Highway Development Organization
Table 9: General specifications of the project
Project Estimated Duration 42 Months
Project Estimated Cost 60,325,299,000 Rials (approximately 1,856,163$)
Starting Date Jul-02
Finishing Date Dec-07
Project Final Duration 65 Months
Project Final Cost 75,323,927,745 Rials (approximately 2,317,659$) Cost Overrun 14,998,628,745 Rials (approximately 461,496$)
Delay 23 Months (Equal to 55% of project estimated
duration)
Terms of Contract 6.4 kilometers highway from kilometer 8+700 to 15+100 with all related construction activities Other Included Structures Twin tunnels with the length of 450 and 400 meters
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6.3 BIM modeling
As the project was designed and planned in Iran, the traditional 2D drafting-centric method was used like all other road and highway projects in Iran. It worth to mention that still there is not any sign of conducting BIM workflow in road construction projects in Iran. This lack of BIM adoption in road construction industry highlights the need
In order to implement BIM workflow for the considered project, three software products were used which will be introduced briefly:
6.3.1 Autodesk Infraworks
This product is the best for easy and quickly preliminary design. It can speed up the design process and help the designer to make a better decision due to better understanding of the project.
6.3.2 AutoCAD Civil 3D
Performing BIM process in roads and highway construction projects starts within the design phase. In this stage, an intelligent 3D model of roadway was generated by means of BIM oriented software product, AutoCAD Civil3D. This software is the key for civil engineering design and documentation. Some features of this software include faster design replication, preparing documentation and sharing and updating information as a collaboration tool; however, these features are not exhaustive.
6.3.3 Autodesk Navisworks Manage
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with the 4th dimension which is time. Some features of Navisworks are mentioned and not limited to the list below:
Planning and sequencing the project;
Detecting clashes and interference checking;
Model reviewing options by creating walk-throughs;and
Creating 5D scheduling, considering cost etc.
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Chapter 7
7
RESULTS AND DISCUSSIONS
7.1 Introduction
In the first part of this chapter, relevant discussions about the findings of the questionnaire survey will be presented. Results of each part of the questionnaire will be checked separately in order to find out the advantages of the positive points. Moreover, cures and recommendations will be proposed for the negative points and disadvantages.
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7.2 Lack of Familiarity with BIM among Iranian Construction
Firms
It is so unreasonable to find out only 20% of the target population know a little about BIM or heard about it before and almost 80% not even have heard the term before. Although 40% chose agree and 60% chose strongly agree on the topic of “efficiency of BIM in preventing time and cost overrun” considering the definitions and a need of change is perceptible in construction management methods, still construction firms prefer to work with the traditional systems as before. There are a number of obstacles which prevent companies to go through a change while almost all of them suffer from excessing time and cost. These obstacles and the extent that BIM can play the role in this issue, especially in developing countries like Iran, are the subjects of next sections.
7.2.1 Advantages of using BIM in road and highway construction
Skanska BIM brochure (2011) mentioned M25 highway widening project around London as a successful sample of implementing BIM workflow in highway projects by using the capabilities in order to finish the project on time. Highway 78 Brawley Bypass project in California is another example of this kind. The latter would be more impressive when it is known that 77% of the projects of that size in the US have faced time overrun due to previous reports (McGraw hill, 2012).
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projects. The numeral benefits can be guesstimated from the previous studies on vertical construction.
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Figure 17: BIM workflow in Design-Tender-Build contracts
Table 9 shows the comparison of the quantities and costs in the bidding and contract documents with the amounts resulted from BIM model. Major measurable items were taken into consideration. Due to the detailed information and subgroups for each item, just the headings were considered. For example, demolition item includes 9 separate subheadings by itself such as removing trees with the diameter up to 60cm, removing trees with the diameter up to 90cm, demolishing buildings, demolishing reinforced concrete etc.; therefore, the units and amounts were not been brought in the table.
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Table 10: Costs of activities in contract documents and BIM model
As the table implies, cost estimations done in BIM procedure in the case study resulted in more accurate estimations in most items; however various accuracy percentages were obtained. In demolition item for instance, BIM estimation is about 40% closer to final cost whereas in formwork item, BIM estimation is only about 7% more than preliminary cost estimations.
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probably would have not happened which would have resulted in a reduction equal to approximate 1,100,000,000 Rials equal to 1.8% of the total project cost. Considering the project finishing date, case study shows 4.7% more accuracy (4.7% closer to reality) in time estimations with BIM.
Figure 18: Highway modelling in AutoCAD Civil3D
But this is not all about the benefits of using BIM models in road and highway construction. As a matter of strong and up to date documentation, there would be less effort needed in the closing phase of the projects and a great deal of time will be saved. Also, an up to date database of the project will be available in case of any need during the operation phase. Unfortunately in this case study, there was not any report available on the delays through the final documentation in the closing phase to be considered.
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7.2.2 Obstacles toward BIM adoption in road and highway construction
Based on the existing literature, by using Focused Group Interview (FGI) method, Gu (2010) listed the challenges of applying BIM as the absence of knowledge and training, the separated character of AEC (Architecture, Engineering and Construction) industry, the existing disaffection between stakeholders to adopt new concepts and the lack of appropriate segmentation in roles and responsibilities between stakeholders. Alternatively in this survey, questionnaire method was used and the results mostly expressed that in Iran, the main cause of not adopting BIM is the lack of knowledge about the new concepts being used in the world. The trend to adopt a new technology is different in various countries. In accordance to the classification defined by Rogers (1995) for new technology adoption, Iran should be considered as laggard applying BIM as a new concept in road construction while questionnaire results demonstrate a rate of almost 100% of projects facing time and cost overrun.
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main difference is that the focus in this survey is on the efficiency of BIM in constructing road and highway within the confined time, budget and desired quality.
7.2.3 Recommendations toward BIM adoption in road construction
In order to eliminate the problem of unfamiliarity with BIM as a new concept among road construction society in Iran, a few recommendations are offered below:
Presenting BIM in construction education as a must: By inserting the trainings of Building Information Modeling in construction pedagogical objectives, in a few years a wide number of fresh experts will be educated to service the construction industry. In some developed countries, the term has been started to be trained during the past few years as an optional course in master degree courses. However, in developing countries like Iran with a very high need of construction after the revolution of 1979, this should be started in the earliest point as a must for the students. Sharag-eldin et al. (2010) assessed the implementation of BIM in AEC education successful in his case study done on Kent State University (KSU) and University of Florida (UF).
